Interactive Coordinate Geometry

This collection contains eight short, teacher-controlled instruments for moments when a board diagram needs motion. Each scene is designed to be built in stages: predict first, reveal the construction, then return to the algebra.

Open the Coordinate Geometry instruments →

Included instruments

1. A Parabola from Focus and Directrix — generate the equal-distance locus point by point.
2. A Parameter Draws a Curve — separate the curve from its parameter, range and direction of travel.
3. Secant to Tangent — watch the secant gradient settle to the tangent gradient.
4. Two Foci, Two Conics — compare the fixed-sum ellipse and fixed-difference hyperbola.
5. Reading the Standard Form — connect parameters with vertices, foci, directrices and asymptotes.
6. Curve-Language Challenge — match constructions, equations, parametrisations and graphs.
7. Eccentricity and Distance Invariants — connect focus-directrix definitions with ellipse and hyperbola distance properties.
8. Conic Sections and Dandelin Spheres — rotate a double cone and reveal how tangent spheres locate the foci.

The instruments work best on a classroom display or laptop. They also include compact layouts for smaller screens.